TW201532138A - Method for etching an etching target layer - Google Patents

Method for etching an etching target layer Download PDF

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TW201532138A
TW201532138A TW103138614A TW103138614A TW201532138A TW 201532138 A TW201532138 A TW 201532138A TW 103138614 A TW103138614 A TW 103138614A TW 103138614 A TW103138614 A TW 103138614A TW 201532138 A TW201532138 A TW 201532138A
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gas
etching
processing
layer
plasma
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TWI629724B (en
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Mitsuru Hashimoto
Takashi Sone
Eiichi Nishimura
Keiichi Shimoda
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Tokyo Electron Ltd
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    • H01L21/02312—Forming insulating materials on a substrate characterised by the treatment performed before or after the formation of the layer pre-treatment treatment by exposure to a gas or vapour
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    • H01L21/306—Chemical or electrical treatment, e.g. electrolytic etching
    • H01L21/3065—Plasma etching; Reactive-ion etching
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    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
    • H01L21/3205—Deposition of non-insulating-, e.g. conductive- or resistive-, layers on insulating layers; After-treatment of these layers
    • H01L21/321—After treatment
    • H01L21/3213—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer
    • H01L21/32133—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer by chemical means only
    • H01L21/32135—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer by chemical means only by vapour etching only
    • H01L21/32136—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer by chemical means only by vapour etching only using plasmas
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    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
    • H01L21/3205—Deposition of non-insulating-, e.g. conductive- or resistive-, layers on insulating layers; After-treatment of these layers
    • H01L21/321—After treatment
    • H01L21/3213—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer
    • H01L21/32139—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer using masks
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Abstract

This invention provides a method for etching an etching target layer of a processing target body. The processing target body has a mask on the etching target layer. The etching target layer and the mask consist of materials showing higher etching efficiency by the plasma of an inert gas with larger atomic number than argon's atomic number, compared with the etching efficiency by the plasma of argon gas. Besides, the mask consists of materials which have higher melting points than the melting point of the etching target layer. For such a processing target body, the method according to this invention includes (a) a process to expose the afore-mentioned processing target body to the plasma of a first processing gas containing a first inert gas with an atomic number which is larger than argon's atomic number, and (b) a process to expose the afore-mentioned processing target body to the plasma of a second processing gas containing a second inert gas with an atomic number which is smaller than argon's atomic number.

Description

被蝕刻層之蝕刻方法Etching method of etched layer

本發明之實施態樣係關於一種蝕刻被蝕刻層的方法。Embodiments of the invention relate to a method of etching an etched layer.

作為使用磁阻效應元件的記憶體元件的一種，具有MTJ（Magnetic Tunnel Junction，磁性穿隧接面）構造的MRAM（Magnetic Random Access Memory，磁性隨機存取記憶體）元件受到吾人注目。As one type of memory element using a magnetoresistance effect element, an MRAM (Magnetic Random Access Memory) element having an MTJ (Magnetic Tunnel Junction) structure has attracted attention.

MRAM元件，包含由含有鐵磁性體等金屬的難以受到蝕刻的材料所構成的多層膜。在該等MRAM元件的製造過程中，例如，有時會用包含Ta（鉭）的遮罩蝕刻PtMn（鉑錳合金）層。該等蝕刻，如日本特開2012－204408號公報所記載的，自以往多使用鹵素氣體。 【先前技術文獻】 【專利文獻】The MRAM device includes a multilayer film composed of a material containing a metal such as a ferromagnetic material that is difficult to be etched. In the manufacturing process of such MRAM devices, for example, a PtMn (platinum manganese alloy) layer may be etched with a mask containing Ta (钽). As described in Japanese Laid-Open Patent Publication No. 2012-204408, a halogen gas has been used in many cases. [Prior Art Literature] [Patent Literature]

【專利文獻1】 日本特開2012－204408號公報[Patent Document 1] Japanese Patent Laid-Open Publication No. 2012-204408

【發明所欲解決的問題】[Problems to be solved by the invention]

然而，在使用鹵素氣體的電漿的蝕刻中，會在該蝕刻所形成之形狀的側壁面堆積反應生成物。另外，由於該反應生成物具有很高的熔點，故難以汽化。若該等堆積物堆積在MRAM元件的MTJ構造的側壁面不除去，會損害到MRAM元件的功能。However, in the etching of the plasma using a halogen gas, the reaction product is deposited on the side wall surface of the shape formed by the etching. Further, since the reaction product has a high melting point, it is difficult to vaporize. If the deposits are deposited on the side wall surface of the MTJ structure of the MRAM device, the function of the MRAM device is impaired.

因此，本案發明人，為了使在之後的處理步驟中的該反應生成物的除去變得更容易，遂嘗試利用含有甲烷氣體以及氬氣的處理氣體作為蝕刻用的氣體。Therefore, in order to make it easier to remove the reaction product in the subsequent processing step, the inventors of the present invention attempted to use a processing gas containing methane gas and argon gas as a gas for etching.

另一方面，MRAM元件的製造過程所採用的蝕刻，要求滿足三個要件，亦即，（1）該蝕刻所形成之形狀的垂直性的提高，（2）該形狀的側壁面所堆積的反應生成物的量，亦即堆積物的量的減少，（3）相對於遮罩的被蝕刻層的蝕刻選擇比的提高。On the other hand, the etching used in the manufacturing process of the MRAM device is required to satisfy three requirements, that is, (1) the improvement of the perpendicularity of the shape formed by the etching, and (2) the reaction of the sidewall surface of the shape. The amount of the product, that is, the decrease in the amount of the deposit, and (3) the improvement of the etching selectivity ratio with respect to the layer to be etched of the mask.

在使用包含甲烷氣體以及氬氣的處理氣體的電漿所進行的蝕刻中，若增加甲烷氣體的量，便可使垂直性以及選擇比提高。然而，堆積物的量也會變多。另一方面，若降低甲烷氣體的量，雖可使堆積物的量減少，然而垂直性以及選擇比也會降低。像這樣，包含甲烷氣體以及氬氣的處理氣體，欲同時滿足三個要件有其技術極限所在。In the etching using a plasma containing a methane gas and a processing gas of argon gas, if the amount of methane gas is increased, the perpendicularity and the selection ratio can be improved. However, the amount of deposits will also increase. On the other hand, if the amount of methane gas is lowered, the amount of deposits can be reduced, but the verticality and the selection ratio are also lowered. As such, a process gas containing methane gas and argon gas has three technical requirements to meet the technical requirements.

因此，在像MRAM元件的製造過程那樣對含有金屬的被蝕刻層所進行的蝕刻中，滿足上述三個要件有其必要。 【解決問題的手段】Therefore, it is necessary to satisfy the above three requirements in the etching of the metal-containing etched layer like the manufacturing process of the MRAM element. [Means for solving problems]

在一態樣中，提供一種蝕刻被處理體的被蝕刻層的方法。被處理體，在被蝕刻層上具有遮罩。被蝕刻層以及遮罩，係由原子序大於氬的原子序的稀有氣體的電漿的蝕刻效率比氬氣的電漿的蝕刻效率更高的材料所構成。另外，遮罩，係由熔點高於被蝕刻層的熔點的材料所構成。對於該等被處理體，本方法包含：使該被處理體暴露於包含原子序大於氬的原子序的第1稀有氣體的第1處理氣體之電漿中的步驟（a）；以及使該被處理體暴露於包含原子序小於氬的原子序的第2稀有氣體的第2處理氣體之電漿中的步驟（b）。在一態樣中，步驟（a）與步驟（b）交替反覆進行。In one aspect, a method of etching an etched layer of a processed object is provided. The object to be processed has a mask on the layer to be etched. The layer to be etched and the mask are composed of a material having a higher etching efficiency of a plasma of a rare gas having an atomic order larger than an atomic order of argon than an argon plasma. Further, the mask is composed of a material having a melting point higher than the melting point of the layer to be etched. For the objects to be processed, the method includes the step (a) of exposing the object to be treated to a plasma of a first processing gas containing a first rare gas having an atomic order greater than an atomic order of argon; and The step (b) of exposing the treatment body to the plasma of the second treatment gas containing the second rare gas having an atomic order smaller than the atomic order of argon. In one aspect, step (a) and step (b) are alternately repeated.

原子序大於氬的原子序的稀有氣體，亦即第1稀有氣體的電漿，對於原子序比較大的材料具有較高的濺鍍效率，亦即，蝕刻效率。因此，包含該第1稀有氣體的第1處理氣體的電漿，比起包含氬氣的處理氣體的電漿而言，可形成垂直性更高的形狀，且可大量除去堆積物。然而，第1處理氣體的電漿，對於遮罩的選擇性較差。另一方面，原子序小於氬的原子序的稀有氣體，亦即第2稀有氣體的電漿，具有較低的濺鍍效率，亦即，蝕刻效率。因此，包含第2稀有氣體的第2處理氣體的電漿，對於原子序較大的材料具有較低的蝕刻效率。然而，第2處理氣體的電漿，對於遮罩的選擇性較佳。A rare gas having an atomic order larger than the atomic order of argon, that is, a plasma of the first rare gas, has a higher sputtering efficiency, that is, an etching efficiency, for a material having a larger atomic order. Therefore, the plasma of the first processing gas containing the first rare gas can form a shape having higher perpendicularity than the plasma containing the processing gas of argon gas, and can remove a large amount of deposits. However, the plasma of the first process gas is less selective for the mask. On the other hand, a rare gas having an atomic order smaller than the atomic order of argon, that is, a plasma of the second rare gas, has a low sputtering efficiency, that is, an etching efficiency. Therefore, the plasma of the second processing gas containing the second rare gas has a low etching efficiency for a material having a large atomic order. However, the plasma of the second process gas is more selective for the mask.

本方法，可藉由將被處理體暴露於第1處理氣體之電漿中的步驟，使蝕刻所形成之形狀的垂直性提高，並且使對該形狀的側壁面所堆積的堆積物減少。另外，本方法，利用將被處理體暴露於第2處理氣體之電漿中的步驟，使相對於遮罩的被蝕刻層的蝕刻選擇比提高。藉由依序實行上述二個步驟，本方法，便可同時滿足上述三個要件。In the method, by exposing the object to be treated to the plasma of the first process gas, the perpendicularity of the shape formed by the etching is improved, and the deposit accumulated on the side wall surface of the shape is reduced. Further, in the present method, the etching selectivity of the layer to be etched with respect to the mask is improved by the step of exposing the object to be treated to the plasma of the second processing gas. By performing the above two steps in sequence, the method can simultaneously satisfy the above three requirements.

另外，被蝕刻層，例如為PtMn層，遮罩，例如為包含Ta的遮罩。另外，第1處理氣體以及第2處理氣體，亦可更包含甲烷氣體。 【發明的功效】Further, the layer to be etched is, for example, a PtMn layer, and the mask is, for example, a mask containing Ta. Further, the first processing gas and the second processing gas may further contain methane gas. [Effect of the invention]

如以上所説明的，在由金屬等原子序比較大的材料所構成的被蝕刻層的蝕刻中，可同時滿足形狀的垂直性的提高、該形狀的側壁面所堆積的堆積物的量的減少、相對於遮罩的被蝕刻層的蝕刻選擇比的提高等要件。As described above, in the etching of the layer to be etched, which is composed of a material having a relatively large atomic order such as a metal, the verticality of the shape can be simultaneously improved, and the amount of deposits deposited on the side wall surface of the shape can be reduced. The improvement of the etching selectivity ratio with respect to the etched layer of the mask.

以下，參照圖式詳細説明各種實施態樣。另外，在各圖式中對於相同或相當的部分會附上相同的符號。Hereinafter, various embodiments will be described in detail with reference to the drawings. In addition, the same symbols are attached to the same or corresponding parts in the drawings.

圖1係表示蝕刻被蝕刻層的方法的一實施態樣的流程圖。圖1所示之方法MT，包含步驟ST1以及步驟ST2。在步驟ST1中，具有被蝕刻層的被處理體（以下稱為「晶圓」），暴露在含有第1稀有氣體的第1處理氣體的電漿中。另外，在步驟ST2中，晶圓暴露在含有第2稀有氣體的第2處理氣體的電漿中。在一實施態樣中，該等步驟ST1以及步驟ST2，亦可交替反覆實行。1 is a flow chart showing an embodiment of a method of etching an etched layer. The method MT shown in FIG. 1 includes step ST1 and step ST2. In step ST1, the object to be processed (hereinafter referred to as "wafer") having the layer to be etched is exposed to the plasma of the first processing gas containing the first rare gas. Further, in step ST2, the wafer is exposed to the plasma of the second processing gas containing the second rare gas. In an embodiment, the steps ST1 and ST2 may be performed alternately and repeatedly.

第1處理氣體所包含的第1稀有氣體，為具有比氬氣的原子序更大的原子序的稀有氣體，例如，Kr氣。另外，第2處理氣體所包含的第2稀有氣體，為具有比氬氣的原子序更小的原子序的稀有氣體，例如，Ne氣。另外，第1處理氣體以及第2處理氣體，更可包含甲烷氣體以及氫氣。The first rare gas contained in the first processing gas is a rare gas having an atomic order larger than the atomic order of argon gas, for example, Kr gas. Further, the second rare gas contained in the second processing gas is a rare gas having an atomic order smaller than the atomic order of argon gas, for example, Ne gas. Further, the first processing gas and the second processing gas may further include methane gas and hydrogen gas.

作為方法MT的適用對象的晶圓，具有被蝕刻層以及設置在該被蝕刻層上的遮罩。被蝕刻層以及遮罩，係由原子序大於氬的原子序的稀有氣體的電漿的蝕刻效率比氬氣的電漿的蝕刻效率更高的材料所構成。另外，遮罩，係由熔點高於被蝕刻層的熔點的材料所構成。只要是該等材料，被蝕刻層以及遮罩，可由任意的材料構成。例如，遮罩，可包含由TiN、Ta、Ti、TaN或W所構成的膜層。另外，被蝕刻層，可為由PtMn、IrMn、CoPd、CoPt、Ru、Mgo、CoFeB、CoFe或Ni所構成的膜層。A wafer to which the method MT is applied has an etched layer and a mask provided on the etched layer. The layer to be etched and the mask are composed of a material having a higher etching efficiency of a plasma of a rare gas having an atomic order larger than an atomic order of argon than an argon plasma. Further, the mask is composed of a material having a melting point higher than the melting point of the layer to be etched. The etched layer and the mask may be composed of any material as long as they are such materials. For example, the mask may comprise a film layer composed of TiN, Ta, Ti, TaN or W. Further, the layer to be etched may be a film layer composed of PtMn, IrMn, CoPd, CoPt, Ru, Mgo, CoFeB, CoFe or Ni.

方法MT，在步驟ST1中，利用第1處理氣體蝕刻被蝕刻層。原子序大於氬的原子序的稀有氣體，亦即第1稀有氣體的電漿，對於原子序比較大的材料具有較高的濺鍍效率，亦即，蝕刻效率。因此，包含該第1稀有氣體的第1處理氣體的電漿，比包含氬氣的處理氣體的電漿，更可形成垂直性較高的形狀，並可大量除去堆積物。然而，第1處理氣體的電漿，對於遮罩的選擇性較差。另一方面，比氬的原子序更小的原子序的稀有氣體，亦即第2稀有氣體的電漿，具有較低的濺鍍效率，亦即，蝕刻效率。因此，包含第2稀有氣體的第2處理氣體的電漿，對於原子序較大的材料具有較低的蝕刻效率。然而，第2處理氣體的電漿，對於遮罩的選擇性較佳。In the method MT, in step ST1, the layer to be etched is etched using the first process gas. A rare gas having an atomic order larger than the atomic order of argon, that is, a plasma of the first rare gas, has a higher sputtering efficiency, that is, an etching efficiency, for a material having a larger atomic order. Therefore, the plasma of the first processing gas containing the first rare gas can form a shape having a higher perpendicularity than the plasma containing the processing gas of argon gas, and can remove a large amount of deposits. However, the plasma of the first process gas is less selective for the mask. On the other hand, a rare gas of an atomic order smaller than the atomic order of argon, that is, a plasma of the second rare gas, has a low sputtering efficiency, that is, an etching efficiency. Therefore, the plasma of the second processing gas containing the second rare gas has a low etching efficiency for a material having a large atomic order. However, the plasma of the second process gas is more selective for the mask.

圖10係表示Ne、Ar、Kr各自的濺鍍率的圖式。具體而言，圖10所示者，係表示具有3000ev的入射能量的Ne離子、Ar離子、Kr離子，分別蝕刻由不同金屬所構成的被蝕刻層的效率，亦即計算出濺鍍率SY（atom／ion）的結果。濺鍍率SY，係在一個離子射入被蝕刻層時，從該被蝕刻層所釋放出的金屬原子的個數。在圖10中，横軸係表示金屬原子的種類，縱軸係表示濺鍍率SY。Fig. 10 is a view showing a sputtering rate of each of Ne, Ar, and Kr. Specifically, as shown in FIG. 10, Ne ions, Ar ions, and Kr ions having an incident energy of 3000 ev are used to etch the efficiency of the etched layer composed of different metals, that is, the sputtering rate SY is calculated. The result of atom/ion). The sputtering rate SY is the number of metal atoms released from the etched layer when one ion is incident on the etched layer. In FIG. 10, the horizontal axis represents the type of metal atom, and the vertical axis represents the sputtering rate SY.

如圖10所示的，Kr離子，對於可構成被蝕刻層的金屬，例如Pt、Mn、Mg、F、Co、Ru等具有較高的濺鍍率SY，亦即較高的濺鍍效率。然而，Kr離子，對於構成遮罩的Ti或Ta也具有1以上的濺鍍率SY。因此，包含Kr此等第1稀有氣體的第1處理氣體，可在被蝕刻層形成垂直性較高的形狀，並可大量除去堆積物。然而，第1處理氣體，對於遮罩的選擇性較差。As shown in FIG. 10, the Kr ion has a high sputtering rate SY, that is, a high sputtering efficiency, for a metal which can constitute an etched layer, for example, Pt, Mn, Mg, F, Co, Ru, or the like. However, the Kr ion also has a sputtering rate SY of 1 or more for Ti or Ta constituting the mask. Therefore, the first processing gas containing the first rare gas such as Kr can form a shape having high perpendicularity in the layer to be etched, and can remove a large amount of deposits. However, the first processing gas has a poor selectivity to the mask.

另一方面，Ne離子，對於可構成被蝕刻層的金屬，例如Pt、Mn、Mg、F、Co、Ru等具有雖低但仍在1以上的濺鍍率SY。另外，Ne離子，對於可構成遮罩的Ti或Ta，具有比1更小的濺鍍率SY。因此，包含Ne此等第2稀有氣體的第2處理氣體，對於可構成被蝕刻層的金屬雖具有較低的蝕刻效率，但仍可蝕刻該金屬。另外，第2處理氣體，實際上不會蝕刻遮罩。On the other hand, the Ne ion has a sputtering rate SY which is low but still 1 or more for a metal which can constitute an etched layer, for example, Pt, Mn, Mg, F, Co, Ru or the like. Further, the Ne ion has a sputtering rate SY smaller than 1 for Ti or Ta which can constitute a mask. Therefore, the second processing gas containing the second rare gas such as Ne has a low etching efficiency for the metal constituting the layer to be etched, but the metal can be etched. Further, the second processing gas does not actually etch the mask.

方法MT，從圖10所示者可知，可利用將晶圓暴露於第1處理氣體之電漿中的步驟，使蝕刻所形成的形狀的垂直性提高，而且，可使對該形狀的側壁面所堆積的堆積物的量減少。另外，可利用將被處理體暴露於第2處理氣體之電漿中的步驟，使相對於遮罩的被蝕刻層的蝕刻選擇比提高。因此，若根據方法MT，藉由依序實行該等二個步驟，便可同時滿足三個要件，亦即，（1）蝕刻所形成之形狀的垂直性的提高、（2）對該形狀的側壁面所堆積的堆積物的量的減少、（3）相對於遮罩的被蝕刻層的蝕刻選擇比的提高。In the method MT, as shown in FIG. 10, the step of exposing the wafer to the plasma of the first processing gas can improve the perpendicularity of the shape formed by the etching, and the side wall surface of the shape can be improved. The amount of accumulated deposits is reduced. Further, the step of exposing the object to be treated to the plasma of the second processing gas can be used to improve the etching selectivity of the layer to be etched with respect to the mask. Therefore, according to the method MT, by performing the two steps in sequence, three elements can be simultaneously satisfied, that is, (1) the improvement of the perpendicularity of the shape formed by the etching, and (2) the side of the shape. The amount of deposits deposited on the wall surface is reduced, and (3) the etching selectivity ratio of the layer to be etched is improved.

圖2係表示適用方法MT的被處理體的一例。圖2所示之被處理體的一例，亦即，晶圓W，為具有MTJ構造的MRAM元件的製造途中所得到的産物。如圖2所示的，晶圓W具有基底層100、被蝕刻層102、MTJ構造104以及上層106。基底層100，在一例中，係作為下部電極的膜層，可由Ta所構成，其厚度為3nm。被蝕刻層102，設置在基底層100上，在一例中，係作為釘紮層的膜層，可由PtMn所構成，其厚度為20nm。另外，上層106，設置在被蝕刻層102的上方，在一例中，包含Ta。上層106的厚度，例如為50nm。MTJ構造104，設置在被蝕刻層102與上層106之間，係由含有鐵磁性材料等金屬的多層膜所構成。MTJ構造104，例如，構成在第1磁性層104a與第2磁性層104b之間具有絶緣層104c的構造。第1磁性層104a以及第2磁性層104b，例如，由CoFeB所構成，各自的厚度為2.5nm。絶緣層104c，例如為MgO層、氧化鋁層、氧化鈦層等的金屬氧化物層，其厚度為1.2nm。另外，晶圓W，更可具有磁性層107以及磁性層108。磁性層107設置在被蝕刻層102上，例如，可由CoFe所構成。磁性層108，設置在磁性層107與MTJ構造104之間，例如，由Ru所構成，其厚度為0.8nm。該晶圓W的被蝕刻層102，為方法MT的蝕刻對象的一例，在方法MT的一應用例中，由上層106、MTJ構造104、磁性層107以及磁性層108所構成的堆疊構造作為遮罩MK，對被蝕刻層102進行蝕刻。FIG. 2 is a view showing an example of a target object to which the method MT is applied. An example of the object to be processed shown in FIG. 2, that is, the wafer W is a product obtained during the manufacture of an MRAM element having an MTJ structure. As shown in FIG. 2, the wafer W has a base layer 100, an etched layer 102, an MTJ structure 104, and an upper layer 106. In the example of the underlayer 100, the film layer as the lower electrode may be made of Ta and has a thickness of 3 nm. The layer to be etched 102 is provided on the underlying layer 100. In one example, the film layer as the pinning layer may be composed of PtMn and has a thickness of 20 nm. Further, the upper layer 106 is provided above the layer to be etched 102, and includes Ta in one example. The thickness of the upper layer 106 is, for example, 50 nm. The MTJ structure 104 is provided between the layer to be etched 102 and the upper layer 106, and is composed of a multilayer film containing a metal such as a ferromagnetic material. The MTJ structure 104 has, for example, a structure having an insulating layer 104c between the first magnetic layer 104a and the second magnetic layer 104b. The first magnetic layer 104a and the second magnetic layer 104b are made of, for example, CoFeB, and each has a thickness of 2.5 nm. The insulating layer 104c is, for example, a metal oxide layer such as a MgO layer, an aluminum oxide layer, or a titanium oxide layer, and has a thickness of 1.2 nm. In addition, the wafer W may further have a magnetic layer 107 and a magnetic layer 108. The magnetic layer 107 is disposed on the layer to be etched 102, for example, may be composed of CoFe. The magnetic layer 108 is disposed between the magnetic layer 107 and the MTJ structure 104, for example, composed of Ru, and has a thickness of 0.8 nm. The etched layer 102 of the wafer W is an example of an etch target of the method MT. In an application example of the method MT, a stacked structure composed of the upper layer 106, the MTJ structure 104, the magnetic layer 107, and the magnetic layer 108 is used as a mask. The mask MK etches the layer 102 to be etched.

以下，針對可用來實施方法MT的電漿處理裝置進行説明。圖3係表示電漿處理裝置的一例。圖3所示的電漿處理裝置10，為電容耦合型的電漿處理裝置。另外，在方法MT的實施中，可使用如感應耦合型的電漿處理裝置、使用微波等表面波的電漿處理裝置等任意的電漿處理裝置。Hereinafter, a plasma processing apparatus that can be used to carry out the method MT will be described. Fig. 3 is a view showing an example of a plasma processing apparatus. The plasma processing apparatus 10 shown in Fig. 3 is a capacitive coupling type plasma processing apparatus. Further, in the implementation of the method MT, any plasma processing apparatus such as an inductively coupled plasma processing apparatus or a plasma processing apparatus using surface waves such as microwaves may be used.

如圖3所示的，電漿處理裝置10，具備處理容器12。處理容器12，具有大略圓筒形狀，其內部空間區劃為處理空間S。電漿處理裝置10，在處理容器12內，具備大略圓板形狀的底座14。底座14，設置在處理空間S的下方。底座14，例如為鋁製，構成下部電極。底座14，具有在處理程序中吸收後述的靜電夾頭50的熱，使靜電夾頭50冷卻的功能。As shown in FIG. 3, the plasma processing apparatus 10 is provided with the processing container 12. The processing container 12 has a substantially cylindrical shape, and its internal space is divided into a processing space S. The plasma processing apparatus 10 has a base 14 having a substantially circular plate shape in the processing container 12. The base 14 is disposed below the processing space S. The base 14 is made of, for example, aluminum and constitutes a lower electrode. The base 14 has a function of absorbing heat of the electrostatic chuck 50 to be described later in the processing program to cool the electrostatic chuck 50.

在底座14的內部，形成了冷媒流路15，冷媒流路15與冷媒入口配管、冷媒出口配管連接。電漿處理裝置10，令適當的冷媒，例如冷卻水等，在冷媒流路15中循環。藉此，將底座14以及靜電夾頭50控制在既定的溫度。Inside the base 14, a refrigerant flow path 15 is formed, and the refrigerant flow path 15 is connected to a refrigerant inlet pipe and a refrigerant outlet pipe. The plasma processing apparatus 10 circulates an appropriate refrigerant, such as cooling water, in the refrigerant flow path 15. Thereby, the base 14 and the electrostatic chuck 50 are controlled at a predetermined temperature.

另外，電漿處理裝置10，更具備筒狀保持部16以及筒狀支持部17。筒狀保持部16，與底座14的側面以及底面的緣部接觸，保持底座14。筒狀支持部17，從處理容器12的底部往垂直方向延伸，隔著筒狀保持部16支持底座14。電漿處理裝置10，更具備載置在該筒狀保持部16的頂面的聚焦環18。聚焦環18，例如，可由矽或石英所構成。Further, the plasma processing apparatus 10 further includes a cylindrical holding portion 16 and a cylindrical support portion 17. The cylindrical holding portion 16 is in contact with the side surface of the base 14 and the edge of the bottom surface, and holds the base 14. The cylindrical support portion 17 extends in the vertical direction from the bottom of the processing container 12, and supports the chassis 14 via the cylindrical holding portion 16. The plasma processing apparatus 10 further includes a focus ring 18 placed on the top surface of the cylindrical holding portion 16. The focus ring 18 can be constructed, for example, of tantalum or quartz.

在一實施態樣中，在處理容器12的側壁與筒狀支持部17之間，形成了排氣通路20。在排氣通路20的入口或其途中，安裝了擋板22。另外，在排氣通路20的底部，設置了排氣口24。排氣口24，係由嵌入處理容器12的底部的排氣管28所形成。該排氣管28，與排氣裝置26連接。排氣裝置26，具有真空泵，可將處理容器12內的處理空間S減壓至既定的真空度。在處理容器12的側壁，安裝了使晶圓W的搬入搬出口開啟或關閉的閘閥30。In one embodiment, an exhaust passage 20 is formed between the side wall of the processing vessel 12 and the cylindrical support portion 17. A baffle 22 is attached to the inlet of the exhaust passage 20 or to the middle thereof. Further, an exhaust port 24 is provided at the bottom of the exhaust passage 20. The exhaust port 24 is formed by an exhaust pipe 28 embedded in the bottom of the processing vessel 12. The exhaust pipe 28 is connected to the exhaust device 26. The exhaust unit 26 has a vacuum pump that decompresses the processing space S in the processing container 12 to a predetermined degree of vacuum. A gate valve 30 that opens or closes the loading/unloading port of the wafer W is attached to the side wall of the processing container 12.

離子牽引用的高頻電源32透過整合器34與底座14電連接。高頻電源32，將適合離子牽引的頻率，例如400KHz的高頻偏壓電力，施加於下部電極，亦即，底座14。The high frequency power source 32 for ion traction is electrically connected to the base 14 through the integrator 34. The high frequency power source 32 applies a frequency suitable for ion traction, for example, a high frequency bias power of 400 KHz, to the lower electrode, that is, the base 14.

電漿處理裝置10，更具備淋浴頭38。淋浴頭38，設置在處理空間S的上方。淋浴頭38，包含電極板40以及電極支持體42。The plasma processing apparatus 10 further includes a shower head 38. The shower head 38 is disposed above the processing space S. The shower head 38 includes an electrode plate 40 and an electrode support 42.

電極板40，為具有大略圓板形狀的導電性板，構成上部電極。電漿生成用的高頻電源35透過整合器36與電極板40電連接。高頻電源35，將電漿生成用的頻率，例如60MHz的高頻電力，供給到電極板40。當利用高頻電源35對電極板40賦予高頻電力時，會在底座14與電極板40之間的空間，亦即處理空間S，形成高頻電場。The electrode plate 40 is a conductive plate having a substantially circular disk shape and constitutes an upper electrode. The high frequency power source 35 for plasma generation is electrically connected to the electrode plate 40 through the integrator 36. The high-frequency power source 35 supplies a frequency for plasma generation, for example, high-frequency power of 60 MHz, to the electrode plate 40. When high-frequency power is applied to the electrode plate 40 by the high-frequency power source 35, a high-frequency electric field is formed in the space between the chassis 14 and the electrode plate 40, that is, the processing space S.

於電極板40形成了複數個氣體通氣孔40h。電極板40以可裝卸的方式受到電極支持體42的支持。在電極支持體42的內部設置了緩衝室42a。電漿處理裝置10，更具備氣體供給部44，緩衝室42a的氣體導入口25透過氣體供給導管46與氣體供給部44連接。氣體供給部44對處理空間S供給處理氣體。氣體供給部44可供給複數種氣體。在一實施態樣中，氣體供給部44可供給甲烷氣體、第1稀有氣體、第2稀有氣體以及氫氣。A plurality of gas vent holes 40h are formed in the electrode plate 40. The electrode plate 40 is detachably supported by the electrode support 42. A buffer chamber 42a is provided inside the electrode support 42. The plasma processing apparatus 10 further includes a gas supply unit 44, and the gas introduction port 25 of the buffer chamber 42a is connected to the gas supply unit 44 through the gas supply conduit 46. The gas supply unit 44 supplies the processing gas to the processing space S. The gas supply unit 44 can supply a plurality of gases. In one embodiment, the gas supply unit 44 can supply methane gas, a first rare gas, a second rare gas, and hydrogen.

在電極支持體42形成了分別與複數個氣體通氣孔40h連接的複數個孔部，該等複數個孔部與緩衝室42a連通。因此，從氣體供給部44所供給的氣體，經由緩衝室42a、氣體通氣孔40h，供給到處理空間S。A plurality of holes respectively connected to the plurality of gas vent holes 40h are formed in the electrode support 42, and the plurality of holes are communicated with the buffer chamber 42a. Therefore, the gas supplied from the gas supply unit 44 is supplied to the processing space S via the buffer chamber 42a and the gas vent 40h.

另外，在電漿處理裝置10的處理容器12的頂板部，設置了以環狀或同心狀延伸的磁場形成機構48。該磁場形成機構48，具有使處理空間S中的高頻放電更容易開始（電漿點火）並維持放電穩定的功能。Further, a magnetic field forming mechanism 48 extending in a ring shape or a concentric shape is provided in the top plate portion of the processing container 12 of the plasma processing apparatus 10. The magnetic field forming mechanism 48 has a function of making the high-frequency discharge in the processing space S easier to start (plasma ignition) and maintaining the discharge stable.

另外，在底座14的頂面之上設置了靜電夾頭50。該靜電夾頭50，包含電極52，還有一對絶緣膜54a以及54b。絶緣膜54a以及54b，係由陶瓷等的絶緣體所形成的膜層。電極52，為導電膜，設置在絶緣膜54a與絶緣膜54b之間。該電極52透過開關SW與直流電源56連接。當從直流電源56對電極52賦予直流電壓時，會產生庫倫力，藉由該庫倫力，晶圓W便被吸附保持在靜電夾頭50上。另外，在靜電夾頭50的內部，埋入了作為加熱元件的加熱器，可將晶圓W加熱到既定溫度。加熱器透過配線與加熱器電源連接。In addition, an electrostatic chuck 50 is disposed above the top surface of the base 14. The electrostatic chuck 50 includes an electrode 52 and a pair of insulating films 54a and 54b. The insulating films 54a and 54b are film layers formed of an insulator such as ceramic. The electrode 52 is a conductive film and is provided between the insulating film 54a and the insulating film 54b. The electrode 52 is connected to the DC power source 56 via a switch SW. When a DC voltage is applied to the electrode 52 from the DC power source 56, a Coulomb force is generated, by which the wafer W is adsorbed and held on the electrostatic chuck 50. Further, a heater as a heating element is embedded in the electrostatic chuck 50, and the wafer W can be heated to a predetermined temperature. The heater is connected to the heater power source through the wiring.

電漿處理裝置10，更具備氣體供給線路58以及60，還有，導熱氣體供給部62以及64。導熱氣體供給部62與氣體供給線路58連接。該氣體供給線路58，延伸到靜電夾頭50的頂面，在該頂面的中央部位以環狀延伸。導熱氣體供給部62，將例如He氣等的導熱氣體，供給到靜電夾頭50的頂面與晶圓W之間。另外，導熱氣體供給部64與氣體供給線路60連接。氣體供給線路60，延伸到靜電夾頭50的頂面，在該頂面以包圍氣體供給線路58的方式環狀延伸。導熱氣體供給部64，將例如He氣等的導熱氣體，供給到靜電夾頭50的頂面與晶圓W之間。The plasma processing apparatus 10 further includes gas supply lines 58 and 60, and heat transfer gas supply units 62 and 64. The heat transfer gas supply unit 62 is connected to the gas supply line 58. The gas supply line 58 extends to the top surface of the electrostatic chuck 50 and extends in a ring shape at a central portion of the top surface. The heat transfer gas supply unit 62 supplies a heat transfer gas such as He gas to the top surface of the electrostatic chuck 50 and the wafer W. Further, the heat transfer gas supply unit 64 is connected to the gas supply line 60. The gas supply line 60 extends to the top surface of the electrostatic chuck 50, and extends annularly around the gas supply line 58 on the top surface. The heat transfer gas supply unit 64 supplies a heat transfer gas such as He gas to the top surface of the electrostatic chuck 50 and the wafer W.

另外，電漿處理裝置10更具備控制部66。該控制部66與排氣裝置26、開關SW、高頻電源32、整合器34、高頻電源35、整合器36、氣體供給部44、導熱氣體供給部62以及64連接。控制部66，分別對排氣裝置26、開關SW、高頻電源32、整合器34、高頻電源35、整合器36、氣體供給部44、導熱氣體供給部62以及64送出控制信號。根據來自控制部66的控制信號，排氣裝置26的排氣、開關SW的開閉、高頻電源32的高頻偏壓電力的供給、整合器34的阻抗調整、高頻電源35的高頻電力的供給、整合器36的阻抗調整、氣體供給部44的處理氣體的供給、導熱氣體供給部62以及64各自的導熱氣體的供給受到控制。Further, the plasma processing apparatus 10 further includes a control unit 66. The control unit 66 is connected to the exhaust unit 26, the switch SW, the high-frequency power source 32, the integrator 34, the high-frequency power source 35, the integrator 36, the gas supply unit 44, and the heat transfer gas supply units 62 and 64. The control unit 66 sends control signals to the exhaust unit 26, the switch SW, the high-frequency power source 32, the integrator 34, the high-frequency power source 35, the integrator 36, the gas supply unit 44, and the heat transfer gas supply units 62 and 64, respectively. The exhaust of the exhaust device 26, the opening and closing of the switch SW, the supply of the high-frequency bias power of the high-frequency power source 32, the impedance adjustment of the integrator 34, and the high-frequency power of the high-frequency power source 35 are based on a control signal from the control unit 66. The supply, the impedance adjustment of the integrator 36, the supply of the processing gas of the gas supply unit 44, and the supply of the heat transfer gas of the heat transfer gas supply units 62 and 64 are controlled.

該電漿處理裝置10，可從氣體供給部44選擇性地對處理空間S供給第1處理氣體以及第2處理氣體。另外，當在第1處理氣體以及第2處理氣體等的處理氣體供給到處理空間S的狀態下，在電極板40與底座14之間，亦即，在處理空間S中形成高頻電場時，會在處理空間S中產生電漿。利用該處理氣體所包含之元素的活性種，對晶圓W的被蝕刻層進行蝕刻。In the plasma processing apparatus 10, the first processing gas and the second processing gas can be selectively supplied to the processing space S from the gas supply unit 44. Further, when the processing gas such as the first processing gas and the second processing gas is supplied to the processing space S, when a high-frequency electric field is formed between the electrode plate 40 and the chassis 14, that is, in the processing space S, A plasma is generated in the processing space S. The layer to be etched of the wafer W is etched by the active species of the elements contained in the processing gas.

以下，針對方法MT的有效性，揭示各種資料進行説明。另外，以下所示的資料，係對圖2所示的晶圓W使用電漿處理裝置10進行蝕刻所取得者。另外，被蝕刻層102，為具有20nm的厚度的PtMn層。另外，上層106為Ta層，上層106與MTJ構造104的總厚度約為50nm。Hereinafter, various materials will be described for the effectiveness of the method MT. In addition, the following information is obtained by etching the wafer W shown in FIG. 2 using the plasma processing apparatus 10. Further, the layer to be etched 102 is a PtMn layer having a thickness of 20 nm. Additionally, the upper layer 106 is a Ta layer, and the total thickness of the upper layer 106 and the MTJ structure 104 is about 50 nm.

［稀有氣體的種類的蝕刻效率］[etching efficiency of rare gas types]

參照圖4。圖4係表示對應稀有氣體的種類的被蝕刻層的蝕刻效率圖。圖4的蝕刻效率，係使處理氣體中的稀有氣體不同所求出者。具體而言，作為稀有氣體，使用了氬（Ar）氣、Kr氣、Ne氣等三種。求出圖4的蝕刻效率時的其他條件，如以下所述。 ＜條件＞ ・處理容器12內壓力：10mTorr（1.333Pa） ・電漿生成用高頻電力：800W ・高頻偏壓電力：1500W ・處理氣體中的氫氣流量：300sccm ・處理氣體中的甲烷氣體流量：90sccm ・處理氣體中的稀有氣體的流量：50sccm ・晶圓溫度：－20℃Refer to Figure 4. Fig. 4 is a graph showing an etching efficiency of an etched layer corresponding to the kind of a rare gas. The etching efficiency of FIG. 4 is obtained by making the rare gas in the processing gas different. Specifically, as the rare gas, three types of argon (Ar) gas, Kr gas, and Ne gas are used. Other conditions at the time of obtaining the etching efficiency of FIG. 4 are as follows. <Conditions> ・Pressure in the processing container 12: 10 mTorr (1.333 Pa) ・High-frequency power for plasma generation: 800 W ・High-frequency bias power: 1500 W ・Hydrogen flow rate in the process gas: 300 sccm ・Methane gas flow rate in the process gas : 90sccm ・Flow of rare gas in the treatment gas: 50sccm ・ Wafer temperature: -20°C

在圖4中，横軸表示處理氣體中的稀有氣體的種類，縱軸表示當使用包含Ar氣的處理氣體的蝕刻率為「1」時使用包含其他稀有氣體的處理氣體的蝕刻率，亦即蝕刻效率。參照圖4，可確認出相對於包含Ar氣的處理氣體而言，包含Kr氣的處理氣體對被蝕刻層102的蝕刻效率較高，另一方面，包含Ne氣的蝕刻氣體對被蝕刻層102的蝕刻效率較低。In FIG. 4, the horizontal axis represents the type of the rare gas in the processing gas, and the vertical axis represents the etching rate of the processing gas containing the other rare gas when the etching rate of the processing gas containing the Ar gas is "1", that is, Etching efficiency. Referring to Fig. 4, it can be confirmed that the etching gas containing the Kr gas has a higher etching efficiency with respect to the layer to be etched 102 than the processing gas containing the Ar gas, and on the other hand, the etching gas containing the Ne gas is applied to the layer 102 to be etched. The etching efficiency is low.

［稀有氣體的種類以及蝕刻時間對形狀的影響］[Types of rare gases and effects of etching time on shape]

參照圖5。圖5係表示稀有氣體的種類以及蝕刻時間對形狀的影響的三個圖式。圖5所示的資料，顯示出在與用來取得圖4之資料的條件相同的條件下蝕刻被蝕刻層102時的形狀與蝕刻時間的相依性。具體而言，在圖5的（a）中，顯示出蝕刻時間（横軸）與角度θ（縱軸）的關係。另外，在圖5的（b）中，顯示出蝕刻時間（横軸）與堆積物的厚度DA（縱軸）的關係。另外，在圖5的（c）中，顯示出蝕刻時間（横軸）與蝕刻後的遮罩MK的厚度MH的關係。另外，如圖6所示的，角度θ，係蝕刻後的被蝕刻層102的側壁面相對於基底層所形成的角度。另外，堆積物的厚度DA，係蝕刻後沿著遮罩MK的側壁面殘留下來的堆積物DP的水平方向的厚度。另外，厚度MH，係蝕刻後所殘留之遮罩MK的膜厚方向的厚度。另外，在圖5中，圖標「Ar氣」，係表示使用包含Ar氣的處理氣體時的資料，圖標「Kr氣」，係表示使用包含Kr氣的處理氣體時的資料，圖標「Ne氣」，係表示使用包含Ar氣的處理氣體時的資料。Refer to Figure 5. Fig. 5 is a view showing three types of the type of rare gas and the influence of etching time on the shape. The data shown in Fig. 5 shows the dependence of the shape and the etching time when the etched layer 102 is etched under the same conditions as those used to obtain the material of Fig. 4. Specifically, in (a) of FIG. 5, the relationship between the etching time (horizontal axis) and the angle θ (vertical axis) is shown. Further, in (b) of FIG. 5, the relationship between the etching time (horizontal axis) and the thickness DA (vertical axis) of the deposit is shown. Further, in (c) of FIG. 5, the relationship between the etching time (horizontal axis) and the thickness MH of the mask MK after etching is shown. Further, as shown in FIG. 6, the angle θ is an angle formed by the side wall surface of the etched layer 102 after etching with respect to the underlying layer. Further, the thickness DA of the deposit is the thickness in the horizontal direction of the deposit DP remaining along the side wall surface of the mask MK after the etching. Further, the thickness MH is the thickness in the film thickness direction of the mask MK remaining after the etching. In addition, in FIG. 5, the icon "Ar gas" indicates the data when the processing gas containing Ar gas is used, and the icon "Kr gas" indicates the data when the processing gas containing Kr gas is used, and the icon "Ne gas" is used. This is the data when using a process gas containing Ar gas.

在用來取得圖5之資料所進行的實驗中，在使用包含Ar氣的處理氣體的情況下、使用包含Kr氣的處理氣體的情況下、使用包含Ne氣的處理氣體的情況下，分別在60秒的蝕刻時間、40秒的蝕刻時間、90秒的蝕刻時間，基底層露出。因此，在使用包含Ar氣的處理氣體的情況下、使用包含Kr氣的處理氣體的情況下、使用包含Ne氣的處理氣體的情況下，分別在60秒以後的蝕刻、40秒以後的蝕刻、90秒以後的蝕刻，為過度蝕刻。In the experiment for obtaining the data of FIG. 5, when a processing gas containing Ar gas is used, when a processing gas containing Kr gas is used, and when a processing gas containing Ne gas is used, The base layer was exposed with an etching time of 60 seconds, an etching time of 40 seconds, and an etching time of 90 seconds. Therefore, when a processing gas containing Ar gas is used, when a processing gas containing Kr gas is used, and when a processing gas containing Ne gas is used, etching is performed after 60 seconds, etching after 40 seconds, and The etching after 90 seconds is over-etching.

參照圖5的（a），在使用包含Ne氣的處理氣體以及包含Ar氣的處理氣體的其中任一種的情況下，角度θ的提高均有其極限，另一方面，在使用包含Kr氣的處理氣體的情況下，可確認出角度θ與蝕刻時間的長度成比例趨近90度的傾向。因此，可確認出，藉由使用包含Kr氣作為稀有氣體的處理氣體，蝕刻所形成之形狀的垂直性會提高。另外，可確認出，藉由使用包含Kr氣的處理氣體，可達到包含Ar氣的處理氣體所無法達到的角度，亦即垂直性。Referring to (a) of FIG. 5, in the case of using any one of a processing gas containing Ne gas and a processing gas containing Ar gas, the increase in the angle θ has its limit, and on the other hand, the use of Kr-containing gas is used. In the case of processing a gas, it was confirmed that the angle θ tends to approach 90 degrees in proportion to the length of the etching time. Therefore, it was confirmed that the verticality of the shape formed by etching was improved by using a processing gas containing Kr gas as a rare gas. Further, it was confirmed that by using the processing gas containing Kr gas, it is possible to achieve an angle which cannot be attained by the processing gas containing Ar gas, that is, perpendicularity.

另外，參照圖5的（b），在使用包含Ne氣的處理氣體以及包含Ar氣的處理氣體的其中任一種的情況下，堆積物DP的厚度DA均較大，另一方面，在使用包含Kr氣的處理氣體的情況下，可確認出堆積物DP的厚度DA與蝕刻時間的長度成比例縮小的傾向。因此，可確認出，藉由使用包含Kr氣作為稀有氣體的處理氣體，可使堆積物的量減少。Further, referring to FIG. 5( b ), when any one of a processing gas containing Ne gas and a processing gas containing Ar gas is used, the thickness DA of the deposit DP is large, and on the other hand, it is included in use. In the case of the Kr gas treatment gas, it was confirmed that the thickness DA of the deposit DP was proportional to the length of the etching time. Therefore, it was confirmed that the amount of the deposit can be reduced by using a processing gas containing Kr gas as a rare gas.

另外，參照圖5的（c），可確認出，在使用包含Kr氣的處理氣體的情況下，遮罩MK的厚度MH縮小，另一方面，在使用包含Ne氣的處理氣體的情況下，遮罩MK的厚度MH變大。因此，可確認出，在使用包含Ne氣的處理氣體的情況下，可維持遮罩MK的膜厚，亦即，可使相對於遮罩MK的被蝕刻層102的選擇性提高。Moreover, referring to (c) of FIG. 5, it can be confirmed that when the processing gas containing Kr gas is used, the thickness MH of the mask MK is reduced, and when the processing gas containing Ne gas is used, The thickness MH of the mask MK becomes large. Therefore, it has been confirmed that when the processing gas containing Ne gas is used, the film thickness of the mask MK can be maintained, that is, the selectivity of the layer to be etched 102 with respect to the mask MK can be improved.

在此，參照圖7説明根據圖4以及圖5的資料所確認到的傾向。圖7的（a），係表示在使用包含Ar氣的處理氣體的情況下的蝕刻後的晶圓的狀態的剖面圖，圖7的（b），係表示在使用包含Ne氣的處理氣體的情況下的蝕刻後的晶圓的狀態的剖面圖，圖7的（c），係表示在使用包含Kr氣的處理氣體的情況下的蝕刻後的晶圓的狀態的剖面圖。Here, the tendency confirmed based on the materials of FIGS. 4 and 5 will be described with reference to FIG. 7. (a) of FIG. 7 is a cross-sectional view showing a state of the wafer after etching using a processing gas containing Ar gas, and (b) of FIG. 7 is a view showing a process gas using Ne gas. The cross-sectional view of the state of the etched wafer in the case, and (c) of FIG. 7 is a cross-sectional view showing the state of the wafer after etching using the processing gas containing Kr gas.

若與使用包含Ar氣的處理氣體時的傾向（參照圖7的（a））作對比，如圖7的（c）所示的，藉由使用包含Kr氣的處理氣體，可使被蝕刻層102的側壁的垂直性提高，且可使堆積物DP的量減少。然而，當使用包含Kr氣的處理氣體時，遮罩MK的膜厚減少，遮罩MK的肩部被削除掉的程度也變大。另外，若與使用包含Ar氣的處理氣體時的傾向作對比，如圖7的（b）所示的，藉由使用包含Ne氣的處理氣體，雖然被蝕刻層102的側壁的垂直性降低，堆積物DP的量也變多，然而卻可維持遮罩MK的膜厚。亦即，藉由使用包含Ne氣的處理氣體，可使相對於遮罩MK的被蝕刻層102的選擇性提高。When compared with the tendency to use a processing gas containing Ar gas (refer to (a) of FIG. 7), as shown in (c) of FIG. 7, the layer to be etched can be formed by using a processing gas containing Kr gas. The verticality of the side wall of 102 is increased, and the amount of deposit DP can be reduced. However, when a processing gas containing Kr gas is used, the film thickness of the mask MK is reduced, and the extent to which the shoulder of the mask MK is removed is also increased. Further, when compared with the tendency when a processing gas containing Ar gas is used, as shown in FIG. 7( b ), by using a processing gas containing Ne gas, although the verticality of the sidewall of the etching layer 102 is lowered, The amount of deposit DP also increases, but the film thickness of the mask MK can be maintained. That is, the selectivity of the layer to be etched 102 with respect to the mask MK can be improved by using a processing gas containing Ne gas.

［稀有氣體的種類以及甲烷氣體的流量對形狀的影響］[The type of rare gas and the influence of the flow rate of methane gas on the shape]

參照圖8。圖8係表示稀有氣體的種類以及甲烷氣體的流量對形狀的影響的三個圖式。圖8所示的資料，係以用來取得圖4之資料的條件為基礎，藉由變更處理氣體中的甲烷氣體的流量所取得。具體而言，在圖8的（a）中，顯示出處理氣體中的甲烷氣體的流量的比例（横軸）與角度θ（縱軸）的關係。另外，在圖8的（b）中，顯示出處理氣體中的甲烷氣體的流量的比例（横軸）與堆積物的厚度DA（縱軸）的關係。另外，在圖8的（c）中，顯示出處理氣體中的甲烷氣體的流量的比例（横軸）與蝕刻後的遮罩MK的厚度MH的關係。另外，在圖8中，圖標「Ar氣」，係表示使用包含Ar氣的處理氣體時的資料，圖標「Kr氣」，係表示使用包含Kr氣的處理氣體時的資料。Refer to Figure 8. Fig. 8 is a view showing three types of the types of rare gases and the influence of the flow rate of methane gas on the shape. The data shown in Fig. 8 is obtained by changing the flow rate of methane gas in the process gas based on the conditions for obtaining the data of Fig. 4. Specifically, in (a) of FIG. 8 , the relationship between the ratio of the flow rate of the methane gas in the processing gas (horizontal axis) and the angle θ (vertical axis) is shown. Further, in (b) of FIG. 8, the relationship between the ratio of the flow rate of the methane gas in the processing gas (horizontal axis) and the thickness DA (vertical axis) of the deposit is shown. Further, in (c) of FIG. 8, the relationship between the ratio of the flow rate of the methane gas in the processing gas (horizontal axis) and the thickness MH of the mask MK after the etching is shown. In addition, in FIG. 8, the icon "Ar gas" is the data at the time of using the process gas containing Ar gas, and the icon "Kr gas" is the data at the time of using the process gas containing Kr gas.

參照圖8的（a），可確認出，在使用包含Ar氣的處理氣體的情況下，若甲烷氣體的流量太多，則垂直性會大幅降低。另一方面，可確認出，在使用包含Kr氣的處理氣體的情況下，與甲烷氣體的流量成比例，垂直性變高。另外，參照圖8的（b），可確認出，與使用包含Ar氣的處理氣體的情況相比，在使用包含Kr氣的處理氣體的情況下，即使甲烷氣體的流量增加，堆積物的量仍較少。另外，參照圖8的（c），可確認出，在使用包含Kr氣的處理氣體的情況下，若使甲烷氣體的流量增加，便可將蝕刻後的遮罩MK的厚度維持在與使用包含Ar氣的處理氣體的情況相等的位準。因此，可確認出，包含Kr氣的處理氣體，可提高垂直性並降低堆積物的量，且可藉由調整甲烷氣體的量，獲得與使用包含Ar氣的處理氣體的情況相等的選擇性。Referring to (a) of FIG. 8, it can be confirmed that when a processing gas containing Ar gas is used, if the flow rate of methane gas is too large, the perpendicularity is largely lowered. On the other hand, when the processing gas containing Kr gas was used, it was confirmed that the verticality became high in proportion to the flow rate of the methane gas. Moreover, referring to (b) of FIG. 8, it can be confirmed that the amount of the deposit is increased even when the flow rate of the methane gas is increased when the processing gas containing the Kr gas is used as compared with the case of using the processing gas containing the Ar gas. Still less. Further, referring to (c) of FIG. 8 , it can be confirmed that when the processing gas containing Kr gas is used, if the flow rate of the methane gas is increased, the thickness of the mask MK after etching can be maintained and used. The processing gas of Ar gas is of the same level. Therefore, it was confirmed that the processing gas containing Kr gas can improve the verticality and reduce the amount of the deposit, and the selectivity equivalent to the case of using the processing gas containing Ar gas can be obtained by adjusting the amount of the methane gas.

［稀有氣體的種類以及高頻偏壓電力對形狀的影響］[Types of rare gases and effects of high-frequency bias power on shape]

參照圖9。圖9係表示稀有氣體的種類以及高頻偏壓電力對形狀的影響的三個圖式。圖9所示的資料，係以用來取得圖4之資料的條件為基礎，藉由變更高頻偏壓電力而取得。在圖9的（a）中，顯示出蝕刻時間（横軸）與角度θ（縱軸）的關係。另外，在圖9的（b）中，顯示出蝕刻時間（横軸）與堆積物的厚度DA（縱軸）的關係。另外，在圖9的（c）中，顯示出蝕刻時間（横軸）與蝕刻後的遮罩MK的厚度MH的關係。另外，在圖9中，圖標「Ar（1500W）」，係表示使用包含Ar氣的處理氣體並供給1500W的高頻偏壓電力時的資料，圖標「Kr（1500W）」，係表示使用包含Kr氣的處理氣體並供給1500W的高頻偏壓電力時的資料，圖標「Kr（1000W）」，係表示使用包含Kr氣的處理氣體並供給1000W的高頻偏壓電力時的資料。Refer to Figure 9. Fig. 9 is a view showing three types of types of rare gases and effects of high-frequency bias power on shape. The data shown in Fig. 9 is obtained by changing the high frequency bias power based on the conditions for obtaining the data of Fig. 4. In (a) of FIG. 9, the relationship between the etching time (horizontal axis) and the angle θ (vertical axis) is shown. Further, in (b) of FIG. 9, the relationship between the etching time (horizontal axis) and the thickness DA (vertical axis) of the deposit is shown. Further, in (c) of FIG. 9, the relationship between the etching time (horizontal axis) and the thickness MH of the mask MK after etching is shown. In addition, in FIG. 9, the icon "Ar (1500W)" is a data when a high-frequency bias electric power of 1500 W is supplied using a process gas containing Ar gas, and the icon "Kr (1500 W)" indicates that the use of Kr is included. The data when the high-frequency bias power of 1500 W is supplied to the gas processing gas, and the icon "Kr (1000 W)" is a data indicating that high-frequency bias power of 1000 W is supplied using a processing gas containing Kr gas.

參照圖9的（a），可確認出，在使用包含Kr氣的處理氣體的情況下，藉由使高頻偏壓電力增大，便可使角度θ擴大，亦即，可使垂直性提高。另外，可確認出，即使為相同的高頻偏壓電力，藉由使用包含Kr氣的處理氣體，與使用包含Ar氣的處理氣體的情況相比，更可獲得較高的垂直性。再者，可確認出，即使使用較低的高頻偏壓電力（1000W），藉由使用包含Kr氣的處理氣體，仍可獲得與使用包含Ar氣的處理氣體以及使用較高的高頻偏壓電力（1500W）的情況相等的垂直性。Referring to (a) of FIG. 9, it can be confirmed that when the processing gas containing Kr gas is used, the angle θ can be increased by increasing the high-frequency bias power, that is, the verticality can be improved. . Further, it was confirmed that even if the same high-frequency bias power is used, by using a processing gas containing Kr gas, higher verticality can be obtained than in the case of using a processing gas containing Ar gas. Furthermore, it was confirmed that even with a low-frequency bias power (1000 W), by using a processing gas containing Kr gas, it is possible to obtain and use a processing gas containing Ar gas and to use a higher high frequency bias. The same verticality of the case of piezoelectric power (1500W).

另外，參照圖9的（b），可確認出，即使高頻偏壓電力較低，藉由使用包含Kr氣的處理氣體，比起包含Ar氣的處理氣體而言，更可使堆積物的量減少。另外，參照圖9的（c），可確認出藉由降低高頻偏壓電力（1000W），即使使用包含Kr氣的處理氣體，仍可將遮罩MK的膜厚維持在與使用包含Ar氣的處理氣體的情況相等的位準。亦即，可確認出，即使使用包含Kr氣的處理氣體，仍可實現與包含Ar氣的處理氣體相等的選擇性。Further, referring to (b) of FIG. 9, it can be confirmed that even if the high-frequency bias power is low, by using the processing gas containing Kr gas, the deposit can be made more than the processing gas containing Ar gas. The amount is reduced. Further, referring to (c) of FIG. 9, it can be confirmed that by reducing the high-frequency bias power (1000 W), even if a processing gas containing Kr gas is used, the film thickness of the mask MK can be maintained and the Ar gas is contained. The level of processing gas is equal. That is, it was confirmed that even if a processing gas containing Kr gas was used, the selectivity equivalent to the processing gas containing Ar gas can be achieved.

總結從以上的資料所確認到的內容，藉由使用包含Kr氣此等第1稀有氣體的第1處理氣體，比起包含Ar氣的處理氣體而言，更可使垂直性提高，並使堆積物的量減少。另外，藉由使用包含第1稀有氣體的第1處理氣體，可將遮罩MK的膜厚維持在與包含Ar氣的處理氣體相等的位準，亦即，可獲得選擇性。另外，藉由使用包含Ne氣此等第2稀有氣體的第2處理氣體，比起使用包含Kr氣或Ar氣的處理氣體的情況而言，更可使選擇性提高。因此，藉由依序實行步驟ST1與步驟ST2，便可滿足三個要件，亦即，垂直性的提高、堆積物的量的減少、選擇性的提高。From the above, it is concluded that by using the first processing gas containing the first rare gas such as Kr gas, the verticality can be improved and the deposition can be increased compared to the processing gas containing the Ar gas. The amount of matter is reduced. Further, by using the first processing gas containing the first rare gas, the film thickness of the mask MK can be maintained at a level equal to that of the processing gas containing Ar gas, that is, selectivity can be obtained. Further, by using the second processing gas containing the second rare gas such as Ne gas, the selectivity can be further improved as compared with the case of using the processing gas containing Kr gas or Ar gas. Therefore, by performing steps ST1 and ST2 in sequence, it is possible to satisfy three requirements, that is, improvement in verticality, reduction in the amount of deposits, and improvement in selectivity.

［實驗例］[Experimental example]

以下，針對實施了方法MT的實驗例進行説明。在該實驗例中，對與圖4資料取得時相同之晶圓，用電漿處理裝置10實施方法MT。另外，作為第1參考例，使用包含Ar氣的處理氣體，對相同的晶圓的被蝕刻層102進行蝕刻。另外，作為第2參考例，使用包含Kr氣的處理氣體，對相同的晶圓的被蝕刻層102進行蝕刻。以下，揭示實驗例、第1參考例、第2參考例的條件。 ＜實驗例的條件＞ ・處理容器12內壓力：10mTorr（1.333Pa） ・電漿生成用高頻電力：800W ・高頻偏壓電力：1500W ・第1處理氣體以及第2處理氣體中的氫氣流量：300sccm ・第1處理氣體以及第2處理氣體中的甲烷氣體流量：90sccm ・第1處理氣體以及第2處理氣體中的稀有氣體的流量：50sccm ・第1稀有氣體：Kr ・第2稀有氣體：Ne ・晶圓溫度：－20℃ ・步驟ST1的時間：10秒 ・步驟ST2的時間：10秒 ・步驟ST1以及步驟ST2所構成之序列的重複次數：5次 ＜第1參考例的條件＞ ・處理容器12內壓力：10mTorr（1.333Pa） ・電漿生成用高頻電力：800W ・高頻偏壓電力：1500W ・處理氣體中的氫氣流量：300sccm ・處理氣體中的甲烷氣體流量：90sccm ・處理氣體中的Ar氣的流量：50sccm ・晶圓溫度：－20℃ ・蝕刻時間：130秒 ＜第2參考例的條件＞ ・處理容器12內壓力：10mTorr（1.333Pa） ・電漿生成用高頻電力：800W ・高頻偏壓電力：1500W ・處理氣體中的氫氣流量：300sccm ・處理氣體中的甲烷氣體流量：90sccm ・處理氣體中的Kr氣的流量：50sccm ・晶圓溫度：－20℃ ・蝕刻時間：130秒Hereinafter, an experimental example in which the method MT is performed will be described. In this experimental example, the method MT was carried out by the plasma processing apparatus 10 for the same wafer as that obtained in the data of FIG. Further, as a first reference example, the etching target layer 102 of the same wafer is etched using a processing gas containing Ar gas. Further, as a second reference example, the etching layer 102 of the same wafer is etched using a processing gas containing Kr gas. Hereinafter, the conditions of the experimental example, the first reference example, and the second reference example are disclosed. <Conditions of the experimental example> The pressure in the processing container 12: 10 mTorr (1.333 Pa) ・High-frequency power for plasma generation: 800 W ・High-frequency bias power: 1500 W ・ Hydrogen flow rate in the first process gas and the second process gas : 300 sccm • The flow rate of the methane gas in the first process gas and the second process gas: 90 sccm • The flow rate of the rare gas in the first process gas and the second process gas: 50 sccm • The first rare gas: Kr • The second rare gas: Ne. Wafer temperature: -20 °C ・Time of step ST1: 10 seconds ・Time of step ST2: 10 seconds ・Number of repetitions of sequence formed by step ST1 and step ST2: 5 times <Conditions of the first reference example> Pressure in the processing container 12: 10 mTorr (1.333 Pa) ・High-frequency power for plasma generation: 800 W ・High-frequency bias power: 1500 W ・Hydrogen flow rate in the processing gas: 300 sccm ・Methane gas flow rate in the processing gas: 90 sccm ・Processing Flow rate of Ar gas in gas: 50 sccm ・Wafer temperature: -20 ° C ・ Etching time: 130 seconds <Condition of the second reference example> ・Pressure in the processing container 12: 10 mTorr (1.333 Pa) ・Electricity High-frequency power: 800W ・High-frequency bias power: 1500W ・Hydrogen flow rate in process gas: 300sccm ・Methane gas flow rate in process gas: 90sccm ・Flow of Kr gas in process gas: 50sccm ・Wafer temperature:- 20 ° C ・ Etching time: 130 seconds

以下，分別針對實驗例、第1參考例、第2參考例，揭示蝕刻後的角度θ、堆積物DP的厚度DA以及蝕刻後的遮罩MK的厚度MH。 ＜實驗例＞ θ：83度 DA：1.5nm MH：35.1nm ＜第1參考例＞ θ：81.5度 DA：4.0nm MH：36.0nm ＜第2參考例＞ θ：84度 DA：0nm MH：24.2nmHereinafter, the angle θ after the etching, the thickness DA of the deposit DP, and the thickness MH of the mask MK after the etching are disclosed for the experimental example, the first reference example, and the second reference example, respectively. <Experimental Example> θ: 83 degrees DA: 1.5 nm MH: 35.1 nm <1st reference example> θ: 81.5 degrees DA: 4.0 nm MH: 36.0 nm <2nd reference example> θ: 84 degrees DA: 0 nm MH: 24.2 Nm

若對比實驗例、第1參考例、第2參考例各自的蝕刻後的角度θ、堆積物的厚度DA以及蝕刻後的遮罩MK的厚度MH，便可清楚確認出，方法MT，可實現在使用包含Ar氣的處理氣體的情況下（第1參考例）不可能實現的位準的垂直性，而且，可使堆積物的量減少。另外，可確認出，方法MT，可將遮罩MK維持在比使用包含Kr氣的處理氣體的情況（第2參考例）更厚的厚度，且與使用包含Ar氣的處理氣體的情況（第1參考例）相等的厚度，亦即，可獲得與使用包含Ar氣的處理氣體的情況相等的選擇性。Comparing the angle θ after etching, the thickness DA of the deposit, and the thickness MH of the mask MK after etching in the experimental example, the first reference example, and the second reference example, it can be clearly confirmed that the method MT can be realized. When the processing gas containing Ar gas is used (the first reference example), the verticality of the level which is impossible to achieve is obtained, and the amount of the deposit can be reduced. In addition, it can be confirmed that the method MT can maintain the mask MK thicker than the case where the processing gas containing the Kr gas is used (the second reference example), and the case where the processing gas containing the Ar gas is used (the 1 Reference Example) Equivalent thickness, that is, selectivity equivalent to the case of using a processing gas containing Ar gas.

以上，係針對各種實施態樣進行説明，惟不限於上述實施態樣，而可構成各種變化態樣。例如，第1處理氣體以及第2處理氣體，係包含甲烷以及氫氣，惟只要是在分別含有第1稀有氣體以及第2稀有氣體，且含有碳以及氫的範圍內，第1處理氣體以及第2處理氣體，實可包含任意的氣體。另外，在上述的實施態樣中，係例示由PtMn所構成的膜層作為被蝕刻層102，惟作為方法MT的蝕刻對象的被蝕刻層，亦可為能夠以上層106作為遮罩進行蝕刻的其他膜層，例如，MTJ構造104所包含的膜層、磁性層107及／或磁性層108。The above description has been made with respect to various embodiments, but it is not limited to the above-described embodiments, and various modifications can be made. For example, the first processing gas and the second processing gas include methane and hydrogen, but the first processing gas and the second are included in the range including the first rare gas and the second rare gas, respectively, and containing carbon and hydrogen. The processing gas may contain any gas. Further, in the above-described embodiment, a film layer made of PtMn is exemplified as the etched layer 102, but the etched layer to be etched by the method MT may be etched by using the upper layer 106 as a mask. Other film layers, for example, a film layer, a magnetic layer 107, and/or a magnetic layer 108 included in the MTJ structure 104.

10‧‧‧電漿處理裝置
12‧‧‧處理容器
14‧‧‧底座
15‧‧‧冷媒流路
16‧‧‧筒狀保持部
17‧‧‧筒狀支持部
18‧‧‧聚焦環
20‧‧‧排氣通路
22‧‧‧擋板
24‧‧‧排氣口
25‧‧‧氣體導入口
26‧‧‧排氣裝置
28‧‧‧排氣管
30‧‧‧閘閥
32‧‧‧高頻電源
34‧‧‧整合器
35‧‧‧高頻電源
36‧‧‧整合器
38‧‧‧淋浴頭
40‧‧‧電極板
42‧‧‧電極支持體
44‧‧‧氣體供給部
46‧‧‧氣體供給導管
48‧‧‧磁場形成機構
50‧‧‧靜電夾頭
52‧‧‧電極
56‧‧‧直流電源
58‧‧‧氣體供給線路
60‧‧‧氣體供給線路
62‧‧‧導熱氣體供給部
64‧‧‧導熱氣體供給部
66‧‧‧控制部
100‧‧‧基底層
102‧‧‧被蝕刻層
104‧‧‧MTJ構造
106‧‧‧上層
107‧‧‧磁性層
108‧‧‧磁性層
104a‧‧‧第1磁性層
104b‧‧‧第2磁性層
104c‧‧‧絶緣層
40h‧‧‧氣體通氣孔
42a‧‧‧緩衝室
54a‧‧‧絶緣膜
54b‧‧‧絶緣膜
DA‧‧‧堆積物的厚度
DP‧‧‧堆積物
MH‧‧‧厚度
MK‧‧‧遮罩
MT‧‧‧方法
S‧‧‧處理空間
ST1‧‧‧步驟
ST2‧‧‧步驟
SW‧‧‧開關
SY‧‧‧濺鍍率
W‧‧‧晶圓10‧‧‧ Plasma processing unit
12‧‧‧Processing container
14‧‧‧Base
15‧‧‧Refrigerant flow path
16‧‧‧Cylinder holding
17‧‧‧Cylinder support
18‧‧‧ Focus ring
20‧‧‧Exhaust passage
22‧‧‧Baffle
24‧‧‧Exhaust port
25‧‧‧ gas inlet
26‧‧‧Exhaust device
28‧‧‧Exhaust pipe
30‧‧‧ gate valve
32‧‧‧High frequency power supply
34‧‧‧ Integrator
35‧‧‧High frequency power supply
36‧‧‧ Integrator
38‧‧‧ shower head
40‧‧‧electrode plate
42‧‧‧electrode support
44‧‧‧Gas Supply Department
46‧‧‧ gas supply conduit
48‧‧‧ Magnetic field forming mechanism
50‧‧‧Electrical chuck
52‧‧‧Electrode
56‧‧‧DC power supply
58‧‧‧ gas supply line
60‧‧‧ gas supply line
62‧‧‧Conducting Heat Supply Department
64‧‧‧Thermal Gas Supply Department
66‧‧‧Control Department
100‧‧‧ basal layer
102‧‧‧etched layer
104‧‧‧MTJ construction
106‧‧‧Upper
107‧‧‧Magnetic layer
108‧‧‧Magnetic layer
104a‧‧‧1st magnetic layer
104b‧‧‧2nd magnetic layer
104c‧‧‧Insulation
40h‧‧‧ gas vents
42a‧‧‧ buffer room
54a‧‧‧Insulation film
54b‧‧‧Insulation film
DA‧‧‧ Thickness of deposits
DP‧‧‧ deposits
MH‧‧ thickness
MK‧‧‧ mask
MT‧‧‧ method
S‧‧‧ processing space
ST1‧‧‧ steps
ST2‧‧‧ steps
SW‧‧ switch
SY‧‧‧ Sputtering rate
W‧‧‧ wafer

【圖1】係表示蝕刻被蝕刻層的方法的一實施態樣的流程圖。 【圖2】係表示適用方法MT的被處理體的一個例圖。 【圖3】係表示電漿處理裝置的一個例圖。 【圖4】係表示對應稀有氣體的種類的被蝕刻層的蝕刻效率圖。 【圖5】(a)~(c)係表示稀有氣體的種類以及蝕刻時間對形狀的影響的三個圖式。 【圖6】係表示形狀的參數圖。 【圖7】(a)~(c)係表示稀有氣體的種類與蝕刻所形成之形狀的傾向圖。 【圖8】(a)~(c)係表示稀有氣體的種類以及甲烷氣體的流量對形狀的影響的三個圖式。 【圖9】(a)~(c)係表示稀有氣體的種類以及高頻偏壓電力對形狀的影響的三個圖式。 【圖10】係表示Ne、Ar、Kr各自的濺鍍率的圖式。Fig. 1 is a flow chart showing an embodiment of a method of etching an etched layer. FIG. 2 is a view showing an example of a target object to which the method MT is applied. Fig. 3 is a view showing an example of a plasma processing apparatus. Fig. 4 is a graph showing an etching efficiency of an etched layer corresponding to the type of a rare gas. Fig. 5 (a) to (c) show three patterns of the type of rare gas and the influence of etching time on the shape. Fig. 6 is a parameter diagram showing a shape. Fig. 7 (a) to (c) show a tendency diagram of the type of a rare gas and the shape formed by etching. Fig. 8 (a) to (c) show three patterns of the types of rare gases and the influence of the flow rate of methane gas on the shape. [Fig. 9] (a) to (c) show three patterns of the type of the rare gas and the influence of the high-frequency bias power on the shape. FIG. 10 is a view showing a sputtering rate of each of Ne, Ar, and Kr.

MT‧‧‧方法 MT‧‧‧ method

ST1‧‧‧步驟 ST1‧‧‧ steps

ST2‧‧‧步驟 ST2‧‧‧ steps

Claims (4)

一種蝕刻被處理體的被蝕刻層的方法，其中： 該被處理體在該被蝕刻層上具有遮罩； 該被蝕刻層以及該遮罩係由後述材料所構成，該材料藉由原子序大於氬的原子序之稀有氣體的電漿之蝕刻效率高於藉由氬氣的電漿之蝕刻效率； 該遮罩係由熔點高於該被蝕刻層的熔點之材料所構成； 該方法包含： 使該被處理體暴露於包含原子序大於氬的原子序之第1稀有氣體的第1處理氣體之電漿中的步驟；以及 使該被處理體暴露於包含原子序小於氬的原子序的第2稀有氣體的第2處理氣體之電漿中的步驟。A method of etching an etched layer of a processed object, wherein: the processed object has a mask on the etched layer; the etched layer and the mask are composed of a material which is larger by atomic order The etching efficiency of the plasma of the rare gas of the atomic order of argon is higher than the etching efficiency of the plasma by argon; the mask is composed of a material having a melting point higher than the melting point of the layer to be etched; the method comprises: a step of exposing the object to be treated to a plasma of a first process gas containing a first rare gas having an atomic order greater than an atomic order of argon; and exposing the object to be treated to a second atom containing an atomic order smaller than argon The step in the plasma of the second process gas of the rare gas. 如申請專利範圍第1項之蝕刻被處理體的被蝕刻層的方法，其中，使該被處理體暴露於該第1處理氣體之電漿中的步驟與使該被處理體暴露於該第2處理氣體之電漿中的步驟交替反覆進行。A method of etching an etched layer of a target object according to the first aspect of the invention, wherein the step of exposing the object to be treated to the plasma of the first process gas and exposing the object to the second The steps in the plasma of the process gas are alternately repeated. 如申請專利範圍第1或2項之蝕刻被處理體的被蝕刻層的方法，其中，該被蝕刻層包含PtMn，該遮罩包含Ta。A method of etching an etched layer of a processed object according to claim 1 or 2, wherein the etched layer comprises PtMn, and the mask comprises Ta. 如申請專利範圍第1或2項之蝕刻被處理體的被蝕刻層的方法，其中，該第1處理氣體以及該第2處理氣體更包含甲烷氣體。A method of etching an etched layer of a target object according to claim 1 or 2, wherein the first process gas and the second process gas further comprise methane gas.
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